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4,692 results on '"Nakai, Y"'

1. Efficient NMR measurement and data analysis supported by the Bayesian inference : The case of the heavy fermion compound YbCo2Zn20

Author

Ueda, H., Katakami, S., Yoshida, S., Nakai, Y., Mito, T., Mizumaki, M., and Okada, M.

Subjects
Condensed Matter - Materials Science
Abstract

We propose a data-driven technique to infer microscopic physical quantities from nuclear magnetic resonance(NMR) spectra, in which the data size and quality required for the Bayesian inference are investigated. The $^{59}$Co-NMR measurement of YbCo$_2$Zn$_{20}$ single crystal generates complex spectra with 28 peaks. By exploiting the site symmetry in the crystal structure, the isotropic Knight shift $K_{iso}$ and nuclear quadrupole resonance(NQR) frequency $\nu_Q$ were estimated to be $K_{iso} = 0.7822 \pm 0.0090 \%$, $\nu_Q = 2.008 \pm 0.016$ MHz ( T = 20 K, H $\simeq$ 10.2 T) by analyzing only 30 data points from one spectrum. The estimation of $\nu_Q$ is consistent with the precise value obtained in the NQR experiment. Our method can significantly reduce the measurement time and the computational cost of data analysis in NMR experiments., Comment: 9 pages

Published
2023

2. Methanol formation through reaction of low energy $CH_{3}^{+}$ ions with an amorphous solid water surface at low temperature

Author

Nakai, Y., Sameera, W. M. C., Furuya, K., Hidaka, H., Ishibashi, A., and Watanabe, N.

Subjects
Astrophysics - Astrophysics of Galaxies, Astrophysics - Instrumentation and Methods for Astrophysics
Abstract

We have performed experimental investigations of methanol formation via the reactions of low energy $CH_{3}^{+}$ ions with an amorphous solid water (ASW) surface around 10 K. A newly developed experimental apparatus enabled irradiation of the ASW surface by several eV ions and detection of trace amounts of reaction products on the surface. It was found that methanol molecules were produced by low-energy $CH_{3}^{+}$ irradiation of the ASW surface and that hydroxy groups in produced methanol originated from water molecules in ASW, as predicted in a previous theoretical study. Little temperature dependence of observed methanol intensity is apparent in the temperature range 12 - 60 K. Ab-initio molecular dynamics simulations under constant temperature conditions of 10 K suggested that this reaction spontaneously produced a methanol molecule and an $H_{3}O^{+}$ ion, regardless of the contact point of $CH_{3}^{+}$ on the ASW surface. We have performed simulation with an astrochemical model under molecular-cloud conditions, where the reaction between $CH_{3}^{+}$ and $H_{2}O$ ice, leading to methanol formation, was included. We found that the impact of the reaction on methanol abundance was limited only at the edge of the molecular cloud (< 1 mag) because of the low abundance of $CH_{3}^{+}$ in the gas phase, whereas the reaction between the abundant molecular ion $HCO^{+}$ and $H_{2}O$ ice, which has not yet been confirmed experimentally, can considerably affect the abundance of a complex organic molecule. This work sheds light on a new type of reaction between molecular ions and ice surfaces that should be included in astrochemical models., Comment: 5 figures and Appendix, accepted to ApJ

Published
2023

3. Direct Determination of the Activation Energy for Diffusion of OH Radicals on Water Ice

Author

Miyazaki, A., Tsuge, M., Hidaka, H., Nakai, Y., and Watanabe, N.

Subjects
Astrophysics - Astrophysics of Galaxies
Abstract

Using a combination of photostimulated desorption and resonance-enhanced multiphoton ionization methods, the behaviors of OH radicals on the surface of interstellar ice analog was monitored at temperatures between 54 and 80 K. The OH number density on the surface of ultraviolet (UV)-irradiated compact amorphous solid water gradually decreased at temperatures above 60 K. Analyzing the temperature dependence of OH intensities with the Arrhenius equation, the decrease can be explained by recombination of two OH radicals, which is rate-limited by thermal diffusion of OH. The activation energy for surface diffusion was experimentally determined for the first time to be 0.14 +/- 0.01 eV, which is larger than or equivalent to those assumed in theoretical models. This value implies that the diffusive reaction of OH radicals starts to be activated at approximately 36 K on interstellar ice., Comment: 5 figures, Accepted to ApJL

Published
2022
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4. Nonmagnetic-magnetic transition and magnetically ordered structure in SmS

Author

Yoshida, S., Koyama, T., Yamada, H., Nakai, Y., Ueda, K., Mito, T., Kitagawa, K., and Haga, Y.

Subjects
Condensed Matter - Strongly Correlated Electrons, Condensed Matter - Materials Science
Abstract

SmS, a prototypical intermediate valence compound, has been studied by performing high-pressure nuclear magnetic resonance measurements on a $^{33}$S-enriched sample. The observation of an additional signal below 15-20 K above a nonmagnetic-magnetic transition pressure $P_{\rm c2} \approx 2$ GPa gives evidence of a magnetic transition. The absence of a Curie-term in the Knight shift near $P_{\rm c2}$ indicates that the localized character of $4f$ electrons is entirely screened and the mechanism of the magnetic ordering is not described within a simple localized model. Simultaneously, the line shape in the magnetically ordered state is incompatible with a spin density wave order. These suggest that the magnetic order in SmS may require an understanding beyond the conventional framework for heavy fermions. The fact that hyperfine fields from the ordered moments cancel out at the S site leads us to a conclusion that the ordered phase has a type II antiferromagnetic structure.

Published
2020
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5. Visible emission spectroscopy of highly charged tungsten ions in LHD: II. Evaluation of tungsten ion temperature

Author

Fujii, K, Takahashi, Y, Nakai, Y, Kato, D, Goto, M, Morita, S, Hasuo, M, and Group, LHD Experiment

Subjects
Physics - Atomic Physics, Physics - Plasma Physics
Abstract

We demonstrated a polarization-resolved high resolution spectroscopy of a visible emission line of highly charged tungsten ions ({\lambda}0 = 668.899 nm, Shinohara et al Phys. Scr. 90 125402) for the large helical device (LHD) plasma, where the tungsten ions were introduced by a pellet injection. Its spectral profile shows broadening and polarization dependence, which are attributed to the Doppler and Zeeman effects, respectively. The tungsten ion temperature was evaluated for the first time from the broadening of visible the emission line, with its emission location determined by the Abel inversion of the chord-integrated emission intensities observed with multiple chords. The tungsten ion temperature was found to be close to the helium-like argon ion temperature, which is used as an ion temperature monitor in LHD

Published
2020
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6. Implications of gravitational waves for supersymmetric grand unification

Author

Chigusa, S, Nakai, Y, and Zheng, J

Abstract

Supersymmetric grand unification based on SO(10) is one of the most attractive paradigms in physics beyond the Standard Model. Inspired by the recent NANOGrav signal, we discuss the implications of detecting a stochastic gravitational wave background emitted by a network of cosmic strings for the SO(10) grand unification. Starting from a minimal model with multiple steps of symmetry breaking, we show that it generally prefers a high intermediate scale above 1014 GeV that is favored by observable primordial gravitational waves. The observed spectrum can potentially narrow the possible range of the cosmic string scale and restricts the unified couplings and the unification scale by requiring gauge coupling unification. As an indirect consequence of the high cosmic string scale, the monopole abundance places nontrivial constraints on the theory. These are complementary to the proton decay constraints and probe different facets of supersymmetric SO(10) unification theories.

Published
2021

8. Pressure induced evolution of band structure in black phosphorus studied by $^{31}$P-NMR

Author

Fujii, T., Nakai, Y., Akahama, Y., Ueda, K., and Mito, T.

Subjects
Condensed Matter - Materials Science, Condensed Matter - Strongly Correlated Electrons
Abstract

Two-dimensional layered semiconductor black phosphorus (BP), a promising pressure induced Dirac system as predicted by band structure calculations, has been studied by $^{31}$P-nuclear magnetic resonance. Band calculations have been also carried out to estimate the density of states $D(E)$. The temperature and pressure dependences of nuclear spin lattice relaxation rate $1/T_1$ in the semiconducting phase are well reproduced using the derived $D(E)$, and the resultant pressure dependence of semiconducting gap is in good accordance with previous reports, giving a good confirmation that the band calculation on BP is fairly reliable. The present analysis of $1/T_1$ data with the complemental theoretical calculations allows us to extract essential information, such as the pressure dependences of $D(E)$ and chemical potential, as well as to decompose observed $1/T_1$ into intrinsic and extrinsic contributions. An abrupt increase in $1/T_1$ at 1.63GPa indicates that the semiconducting gap closes, resulting in an enhancement of conductivity., Comment: 11 pages, 4 figures

Published
2019
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9. Evidence for gradual evolution of low-energy fluctuations underlying the first-order structural and valence order in YbPd

Author

Nakanishi, R., Fujii, T., Nakai, Y., Ueda, K., Hirata, M., Oyama, K., Mitsuda, A., Wada, H., and Mito, T.

Subjects
Condensed Matter - Strongly Correlated Electrons
Abstract

The valence orders at $T_a=125$ K and $T_b=105$ K in the cubic compound YbPd have been investigated by $^{105}$Pd-nuclear magnetic resonance (NMR) measurements. Significant decrease in the density of states at the Fermi energy below $T_a$ is evident from the measurement of nuclear spin lattice relaxation rate $1/T_1$, suggesting that the instabilities of Fermi surface are associated with the transitions. Moreover we observed the unusual evolution of low-energy fluctuations toward the valence transition at $T_a$ behind its drastic first-order nature. The structural transition accompanying the valence order may occur as a result of cooperative effect of Fermi surface and valence instabilities., Comment: 5 pages, 3 figures

Published
2019

10. COMET Phase-I Technical Design Report

Author

The COMET Collaboration, Abramishvili, R., Adamov, G., Akhmetshin, R. R., Allin, A., Angélique, J. C., Anishchik, V., Aoki, M., Aznabayev, D., Bagaturia, I., Ban, G., Ban, Y., Bauer, D., Baygarashev, D., Bondar, A. E., Cârloganu, C., Carniol, B., Chau, T. T., Chen, J. K., Chen, S. J., Cheung, Y. E., da Silva, W., Dauncey, P. D., Densham, C., Devidze, G., Dornan, P., Drutskoy, A., Duginov, V., Eguchi, Y., Epshteyn, L. B., Evtoukhovich, P., Fayer, S., Fedotovich, G. V., Finger Jr, M., Finger, M., Fujii, Y., Fukao, Y., Gabriel, J. L., Gay, P., Gillies, E., Grigoriev, D. N., Gritsay, K., Hai, V. H., Hamada, E., Hashim, I. H., Hashimoto, S., Hayashi, O., Hayashi, T., Hiasa, T., Ibrahim, Z. A., Igarashi, Y., Ignatov, F. V., Iio, M., Ishibashi, K., Issadykov, A., Itahashi, T., Jansen, A., Jiang, X. S., Jonsson, P., Kachelhoffer, T., Kalinnikov, V., Kaneva, E., Kapusta, F., Katayama, H., Kawagoe, K., Kawashima, R., Kazak, N., Kazanin, V. F., Kemularia, O., Khvedelidze, A., Koike, M., Kormoll, T., Kozlov, G. A., Kozyrev, A. N., Kravchenko, M., Krikler, B., Kumsiashvili, G., Kuno, Y., Kuriyama, Y., Kurochkin, Y., Kurup, A., Lagrange, B., Lai, J., Lee, M. J., Li, H. B., Litchfield, R. P., Li, W. G., Loan, T., Lomidze, D., Lomidze, I., Loveridge, P., Macharashvili, G., Makida, Y., Mao, Y. J., Markin, O., Matsuda, Y., Melkadze, A., Melnik, A., Mibe, T., Mihara, S., Miyamoto, N., Miyazaki, Y., Idris, F. Mohamad, Azmi, K. A. Mohamed Kamal, Moiseenko, A., Moritsu, M., Mori, Y., Motoishi, T., Nakai, H., Nakai, Y., Nakamoto, T., Nakamura, Y., Nakatsugawa, Y., Nakazawa, Y., Nash, J., Natori, H., Niess, V., Nioradze, M., Nishiguchi, H., Noguchi, K., Numao, T., O'Dell, J., Ogitsu, T., Ohta, S., Oishi, K., Okamoto, K., Okamura, T., Okinaka, K., Omori, C., Ota, T., Pasternak, J., Paulau, A., Picters, D., Ponariadov, V., Quémener, G., Ruban, A. A., Rusinov, V., Sabirov, B., Sakamoto, H., Sarin, P., Sasaki, K., Sato, A., Sato, J., Semertzidis, Y. K., Shigyo, N., Shoukavy, Dz., Slunecka, M., Stöckinger, D., Sugano, M., Tachimoto, T., Takayanagi, T., Tanaka, M., Tang, J., Tao, C. V., Teixeira, A. M., Tevzadze, Y., Thanh, T., Tojo, J., Tolmachev, S. S., Tomasek, M., Tomizawa, M., Toriashvili, T., Trang, H., Trekov, I., Tsamalaidze, Z., Tsverava, N., Uchida, T., Uchida, Y., Ueno, K., Velicheva, E., Volkov, A., Vrba, V., Abdullah, W. A. T. Wan, Warin-Charpentier, P., Wong, M. L., Wong, T. S., Wu, C., Xing, T. Y., Yamaguchi, H., Yamamoto, A., Yamanaka, M., Yamane, T., Yang, Y., Yano, T., Yao, W. C., Yeo, B., Yoshida, H., Yoshida, M., Yoshioka, T., Yuan, Y., Yudin, Yu. V., Zdorovets, M. V., Zhang, J., Zhang, Y., and Zuber, K.

Subjects
Physics - Instrumentation and Detectors, High Energy Physics - Experiment
Abstract

The Technical Design for the COMET Phase-I experiment is presented in this paper. COMET is an experiment at J-PARC, Japan, which will search for neutrinoless conversion of muons into electrons in the field of an aluminium nucleus ($\mu-e$ conversion, $\mu^- N \to e^- N$); a lepton flavor violating process. The experimental sensitivity goal for this process in the Phase-I experiment is $3.1\times10^{-15}$, or 90 % upper limit of branching ratio of $7\times 10^{-15}$, which is a factor of 100 improvement over the existing limit. The expected number of background events is 0.032. To achieve the target sensitivity and background level, the 3.2 kW 8 GeV proton beam from J-PARC will be used. Two types of detectors, CyDet and StrECAL, will be used for detecting the \mue conversion events, and for measuring the beam-related background events in view of the Phase-II experiment, respectively. Results from simulation on signal and background estimations are also described., Comment: A minor correction applied in Eq. 3

Published
2018
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12. Significant Improvement of Prognosis After the Advent of Immune Checkpoint Inhibitors in Patients with Advanced, Unresectable, or Metastatic Urothelial Carcinoma: A Propensity Score Matching and Inverse Probability of Treatment Weighting Analysis on Real-World Data

Author

Miyake M, Nishimura N, Shimizu T, Ohnishi M, Kuwada M, Itami Y, Inoue T, Ohnishi K, Matsumoto Y, Yoshida T, Tatsumi Y, Shinohara M, Hori S, Morizawa Y, Gotoh D, Nakai Y, Anai S, Torimoto K, Aoki K, Fujii T, Tanaka N, and Fujimoto K

Subjects
urinary bladder neoplasms, immunotherapy, chemotherapy, survival, propensity score, Neoplasms. Tumors. Oncology. Including cancer and carcinogens, RC254-282
Abstract

Makito Miyake,1 Nobutaka Nishimura,1,2 Takuto Shimizu,1,3 Mikiko Ohnishi,4 Masaomi Kuwada,4 Yoshitaka Itami,5 Takeshi Inoue,5 Kenta Ohnishi,6 Yoshihiro Matsumoto,6 Takanori Yoshida,7 Yoshihiro Tatsumi,8 Masatake Shinohara,9 Shunta Hori,1 Yosuke Morizawa,1 Daisuke Gotoh,1 Yasushi Nakai,1 Satoshi Anai,1 Kazumasa Torimoto,1 Katsuya Aoki,1 Tomomi Fujii,10 Nobumichi Tanaka,1,11 Kiyohide Fujimoto1 1Department of Urology, Nara Medical University, Kashihara, Nara, 634-8522, Japan; 2Department of Urology, Okanami General Hospital, Iga, Mie, Japan; 3Department of Urology, Saiseikai Chuwa Hospital, Nara, Japan; 4Department of Urology, Matsusaka Chuo General Hospital, Matsusaka, Mie, Japan; 5Department of Urology, Nara Prefecture General Medical Center, Nara, Japan; 6Department of Urology, Hoshigaoka Medical Center, Hirakata, Osaka, Japan; 7Department of Urology, Tane General Hospital, Osaka, Japan; 8Department of Urology, JCHO Yamato Koriyama Hospital, Koriyama, Nara, Japan; 9Department of Urology, Osaka Gyoumeikan Hospital, Osaka, Japan; 10Department of Diagnostic Pathology, Nara Medical University, Kashihara, Nara, 634-8522, Japan; 11Department of Prostate Brachytherapy, Nara Medical University, Kashihara, Nara, 634-8522, JapanCorrespondence: Makito Miyake, Department of Urology, Nara Medical University, 840 Shijo-cho, Nara, 634-8522, Japan, Tel +81-744-22-3051 (ext 2338), Fax +81-744-22-9282, Email makitomiyake@yahoo.co.jpPurpose: The treatment landscape for advanced, unresectable, or metastatic urothelial carcinoma (aUC) has shifted substantially since the advent of immune checkpoint inhibitors (ICIs). We investigated the extent to which pembrolizumab therapy is superior to conventional chemotherapy as a second-line treatment.Patients and Methods: A multicenter-derived database registered 454 patients diagnosed with aUC between 2008 and 2020. Of these, 94 patients (21%) who received second-line pembrolizumab and 75 (17%) who received second-line chemotherapy but never received third-line or later ICI therapy were included. We compared overall survival (OS) from the initial date of first-line chemotherapy between two groups by adjusting for prognostic factors through propensity score matching (PSM) and inverse probability of treatment weighting (IPTW). The IPTW-adjusted hazard ratio and 95% confidence interval were estimated using a multivariate Cox regression analysis. To identify patients who were more likely to benefit from second-line pembrolizumab than from chemotherapy, we performed a subgroup analysis for OS with an IPTW-adjusted model.Results: The PSM-adjusted comparison showed a significant improvement in the prognosis with second-line pembrolizumab use (P = 0.01). The OS benefit with the advent of pembrolizumab was 8 months (18 months vs 26 months). Multivariable analyses using IPTW adjustment demonstrated that lymph node metastasis (P = 0.001), lung metastasis (P = 0.013), and bone metastasis (P = 0.003) were poor independent prognostic factors, and pembrolizumab use (P = 0.021) was a favorable independent prognostic factor. Subgroup analyses revealed that pembrolizumab was associated with survival benefits over chemotherapy in all subgroups, including young patients (age < 70 years), those who received radical surgery, and those without visceral metastasis.Conclusion: We demonstrated a significant improvement in prognosis after the advent of pembrolizumab for patients with aUC. ICIs should not be restricted based on patient characteristics.Keywords: urinary bladder neoplasms, immunotherapy, chemotherapy, survival, propensity score

Published
2022

13. Anti-PD-1 antibody monotherapy versus anti-PD-1 plus anti-CTLA-4 combination therapy as first-line immunotherapy in unresectable or metastatic mucosal melanoma: a retrospective, multicenter study of 329 Japanese cases (JMAC study)

Author

Nakamura, Y., Namikawa, K., Yoshikawa, S., Kiniwa, Y., Maekawa, T., Yamasaki, O., Isei, T., Matsushita, S., Nomura, M., Nakai, Y., Fukushima, S., Saito, S., Takenouchi, T., Tanaka, R., Kato, H., Otsuka, A., Matsuya, T., Baba, N., Nagase, K., Inozume, T., Fujimoto, N., Kuwatsuka, Y., Onishi, M., Kaneko, T., Onuma, T., Umeda, Y., Ogata, D., Takahashi, A., Otsuka, M., Teramoto, Y., and Yamazaki, N.

Published
2021
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15. Effect of Prolonged Duration of Transrectal Ultrasound-Guided Biopsy of the Prostate and Pre-Procedure Anxiety on Pain in Patients without Anesthesia

Author

Nakai Y, Tanaka N, Matsubara T, Anai S, Miyake M, Hori S, Fujii T, Ohbayashi C, and Fujimoto K

Subjects
anesthesia, anxiety, biopsy, pain, prostate cancer, Diseases of the genitourinary system. Urology, RC870-923
Abstract

Yasushi Nakai,1 Nobumichi Tanaka,1 Toshihiko Matsubara,1 Satoshi Anai,1 Makito Miyake,1 Shunta Hori,1 Tomomi Fujii,2 Chiho Ohbayashi,2 Kiyohide Fujimoto1 1Department of Urology, Nara Medical University, Nara, Japan; 2Department of Diagnostic Pathology, Nara Medical University, Nara, JapanCorrespondence: Nobumichi TanakaDepartment of Urology, Nara Medical University, 840 Shijo-cho, Nara, 634-8522, JapanTel +81-744-22-3051 (ext. 2338)Fax +81-744-22-9282Email sendo@naramed-u.ac.jpObjective: To evaluate factors correlated with pain during prostate biopsy and willingness to undergo transrectal ultrasound-guided prostate biopsy (TR-PBx) again without anesthesia in patients undergoing TR-PBx without anesthesia.Methods: This retrospective, single-center study evaluated 624 patients who underwent TR-PBx without anesthesia. Based on a nomogram using patient age and prostate volume, 6– 12 core biopsy samples were allocated. Anxiety was evaluated using the Faces Anxiety Scale before the TR-PBx. Pain was evaluated using the Faces Pain Scale at each puncture and immediately after confirmation of cessation of bleeding from the rectum after the transrectal probe was pulled out. The question “If this operation must be repeated, would you agree to undergo it again under same conditions?” was asked after the procedure was completed. The change in pain at each puncture and factors correlated with post-procedural pain were calculated using multiple regression analysis, and factors predicting an answer of “yes” to the question using binary logistic analysis were evaluated.Results: Scores on the Faces Pain Scale significantly increased from the first core sample to last as the number of samples increased. However, the number of samples did not show significant correlation with pain evaluated after the procedure was complete. Time during the biopsy and the anxiety score had a significant correlation with the pain scale score for the completed procedure. Short duration of TR-biopsy and a low anxiety score predicted a reply of “Yes” to the question.Conclusion: A long operative time during the TR-PBx procedure and strong pre-procedure anxiety can increase pain for patients undergoing the procedure without anesthesia and cause patients to be unwilling to undergo TR-PBx again without anesthesia.Keywords: anesthesia, anxiety, biopsy, pain, prostate cancer

Published
2021

16. Impact of Radical Nephrectomy and Partial Nephrectomy on Actual Estimated Overall Survival Compared to Life Expectancy in Patients with Renal Cell Carcinoma

Author

Hori S, Tanaka N, Iida K, Nakai Y, Miyake M, Anai S, Torimoto K, and Fujimoto K

Subjects
life expectancy, nephrectomy, performance status, renal cell carcinoma, tumor size, Diseases of the genitourinary system. Urology, RC870-923
Abstract

Shunta Hori, Nobumichi Tanaka, Kota Iida, Yasushi Nakai, Makito Miyake, Satoshi Anai, Kazumasa Torimoto, Kiyohide Fujimoto Department of Urology, Nara Medical University, Kashihara, Nara, 634-8522, JapanCorrespondence: Nobumichi TanakaDepartment of Urology, Nara Medical University, 840 Shijo-cho, Kashihara, Nara, 634-8522, JapanTel +81-744-22-3051Fax +81-744-22-9282Email sendo@naramed-u.ac.jpPurpose: Reports suggest that partial nephrectomy provides no significant benefit in terms of cancer-specific and overall survival (OS) compared to radical nephrectomy. Here, we focused on survival in terms of life expectancy and investigated the significance of partial nephrectomy for localized renal cell carcinoma (RCC) patients.Patients and Methods: Our retrospective study included 937 patients (median age 63 years) with localized RCC who underwent partial nephrectomy or radical nephrectomy. Various predictive factors were explored, and the association between actual OS and life expectancy was analyzed.Results: Performance status (PS) ≥ 1 and tumor size ≥ 40 mm were identified as independent poor prognostic factors for cancer-specific survival. Age ≥ 60, male sex, PS ≥ 1, C-reactive protein elevation, pT1b stage, and radical nephrectomy were identified as independent poor prognostic factors for OS. OS and life expectancy did not differ in the partial nephrectomy group (P=0.11). OS was significantly shorter than life expectancy in the radical nephrectomy group (P< 0.0001). In PS0 or pT1a patients, there was a significant difference between actual OS and life expectancy in the radical nephrectomy group (P< 0.0001), but not in the partial nephrectomy group (P=0.15). In patients with a life expectancy ≥ 10 years, PS0, and pTa, OS and life expectancy differed in the radical nephrectomy group, but not in the partial nephrectomy group.Conclusion: Partial nephrectomy can improve actual OS, and notably, PS and tumor size are crucial factors that determine the choice of surgical procedure. Further research is needed to establish appropriate treatment strategies and criteria for clinical practice.Keywords: life expectancy, nephrectomy, performance status, renal cell carcinoma, tumor size

Published
2021

18. Beam energy dependence of charged pion ratio in $^{28}$Si + In reactions

Author

Sako, M., Murakami, T., Nakai, Y., Ichikawa, Y., Ieki, K., Imajo, S., Isobe, T., Matsushita, M., Murata, J., Nishimura, S., Sakurai, H., Sameshima, R. D., and Takada, E.

Subjects
Nuclear Experiment
Abstract

The double differential cross sections for $^{nat}$In($^{28}$Si, $\pi ^{\pm}$) reactions are measured at 400, 600, and 800 MeV/nucleon. Both $\pi^+$ and $\pi^-$ are found to be emitted isotropically from a single moving source. The $\pi^- / \pi^+$ yield ratio is determined as a function of the charged pion energy between 25 and 100 MeV. The experimental results significantly differ from the prediction of the standard transport model calculation using the code PHITS. This discrepancy suggests that more theoretical works are required to deduce firm information on the nuclear symmetry energy from the $\pi^- / \pi^+$ yield ratio., Comment: 6 pages, 4 figures

Published
2014

19. Trends in the Treatment Outcomes and Features of Cryptorchidism in Boys: A Single-Institute Experience

Author

Hori S, Aoki K, Nishimura N, Morizawa Y, Gotoh D, Fukui S, Nakai Y, Miyake M, Torimoto K, and Fujimoto K

Subjects
cryptorchidism, hypospadias, orchiopexy, pediatrics, spontaneous resolution, Diseases of the genitourinary system. Urology, RC870-923
Abstract

Shunta Hori, Katsuya Aoki, Nobutaka Nishimura, Yosuke Morizawa, Daisuke Gotoh, Shinji Fukui, Yasushi Nakai, Makito Miyake, Kazumasa Torimoto, Kiyohide Fujimoto Department of Urology, Nara Medical University, Kashihara, Nara 634-8522, JapanCorrespondence: Kiyohide FujimotoDepartment of Urology, Nara Medical University, 840 Shijo-cho, Kashihara, Nara 634-8522, JapanTel +81-744-22-3051Fax +81-744-22-9282Email kiyokun@naramed-u.ac.jpPurpose: Cryptorchidism is one of the most common congenital abnormalities in pediatric urology, and orchiopexy is performed for the prevention of testicular damage and malignant transformation. We examined the distribution and outcomes of cryptorchidism under a single investigator at our institute.Patients and Methods: This retrospective study included 283 boys diagnosed with cryptorchidism at our institute. Cryptorchidism was diagnosed based on the medical history and physical examination findings. Boys without spontaneous resolution after 6 months of age were indicated for orchiopexy. We investigated the 12-year trend in the distribution and outcomes of cryptorchidism at the institute.Results: The mean age at diagnosis, gestational age, and birth weight were 2 years, 37 weeks, and 2740 g, respectively. A total of 170 boys underwent orchiopexy under 2 years of age, and 136 boys underwent orchiopexy under the age of 1 year, while 62 boys underwent orchiopexy over the age of 3 years. Abnormalities of the epididymis and disclosure of the processus vaginalis were observed in 44 (25%) and 72 boys (41%), respectively. Comparison of boys with or without hypospadias showed that the age at orchiopexy was higher in boys with hypospadias than in those without hypospadias (P=0.028). In addition, boys without hypospadias had a higher rate of abnormality of the epidermis than those with hypospadias (P=0.024).Conclusion: Our findings suggest that most boys with cryptorchidism are treated under the age of 2 years and the incidence of epididymal abnormality is relatively high, especially in boys with hypospadias. An understanding of the natural features of cryptorchidism could lead to better management and outcomes. Further research is warranted to develop an appropriate treatment timeline in boys with cryptorchidism.Keywords: cryptorchidism, hypospadias, orchiopexy, pediatrics, spontaneous resolution

Published
2020

20. Is Endoscopic Transurethral Incision Really Effective for Boys with Refractory Daytime Incontinence?

Author

Morizawa Y, Aoki K, Hori S, Gotoh D, Miyake M, Nakai Y, Torimoto K, Tanaka N, and Fujimoto K

Subjects
pediatric, daytime incontinence, enuresis, tui, Diseases of the genitourinary system. Urology, RC870-923
Abstract

Yosuke Morizawa, Katsuya Aoki, Shunta Hori, Daisuke Gotoh, Makito Miyake, Yasushi Nakai, Kazumasa Torimoto, Nobumichi Tanaka, Kiyohide Fujimoto Department of Urology, Nara Medical University, Kashihara, Nara, JapanCorrespondence: Kiyohide FujimotoDepartment of Urology, Nara Medical University, 840 Shijo-cho, Kashihara, Nara 634-8522, JapanTel +81-744-22-3051Fax +81-744-22-9282Email kiyokun@naramed-u.ac.jpPurpose: To determine the clinical efficacy of endoscopic transurethral incision (TUI) for boys with refractory daytime incontinence due to a posterior urethral valve with or without nocturnal enuresis.Patients and Methods: A total of 20 boys with daytime incontinence were assessed. Twelve boys underwent TUI (TUI+ group) and eight boys continued receiving oral drugs (TUI- group). The primary endpoint was the cure rate associated with TUI or NE in both groups.Results: Only two boys achieved daytime continence 6 months after TUI, but no boys were cured of nocturnal enuresis 6 months after TUI. The median time to daytime continence was significantly longer in the TUI+ than in the TUI- group (52 vs 27 months, respectively; log rank P = 0.041) and the median time to dry nights was significantly longer in the TUI+ than in the TUI- group (56 vs 36 months, respectively; log rank P = 0.021).Conclusion: TUI might be not effective in boys with refractory daytime incontinence.Keywords: pediatric, daytime incontinence, enuresis, TUI

Published
2020

21. Normal state spin dynamics in the iron-pnictide superconductors BaFe2(As1-xPx)2 and Ba(Fe1-xCox)2As2 probed with NMR measurements

Author

Nakai, Y., Iye, T., Kitagawa, S., Ishida, K., Kasahara, S., Shibauchi, T., Matsuda, Y., Ikeda, H., and Terashima, T.

Subjects
Condensed Matter - Superconductivity, Condensed Matter - Strongly Correlated Electrons
Abstract

The NMR results in iron pnictides BaFe2(As1-xPx)2 and Ba(Fe1-xCox)2As2 are analyzed based on the self-consistent renormalization (SCR) spin fluctuation theory. The temperature dependence of the NMR relaxation rate (T_1)^{-1} as well as the electrical resistivity is well reproduced by a SCR model where two-dimensional antiferromagnetic (AF) spin fluctuations are dominant. The successful description of the crossover feature from non-Fermi liquid to Fermi liquid behavior strongly suggests that low-lying spin fluctuations in BaFe2(As1-xPx)2 and Ba(Fe1-xCox)2As2 possess an itinerant AF nature, and that chemical substitution in the two compounds tunes the distance of these systems to an AF quantum critical point. The close relationship between spin fluctuations and superconductivity is discussed compared with the other unconventional superconductors, cuprate and heavy fermion superconductors. In addition, it is suggested that magnetism and lattice instability in these pnictides are strongly linked via orbital degrees of freedom., Comment: 11 pages, 14 figures

Published
2013
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22. Superconductivity induced by longitudinal ferromagnetic fluctuations in UCoGe

Author

Hattori, T., Ihara, Y., Nakai, Y., Ishida, K., Tada, Y., Fujimoto, S., Kawakami, N., Osaki, E., Deguchi, K., Sato, N. K., and Satoh, I.

Subjects
Condensed Matter - Superconductivity, Condensed Matter - Strongly Correlated Electrons
Abstract

From detailed angle-resolved NMR and Meissner measurements on a ferromagnetic (FM) superconductor UCoGe (T_Curie ~ 2.5 K and T_SC ~ 0.6 K), we show that superconductivity in UCoGe is tightly coupled with longitudinal FM spin fluctuations along the c axis. We found that magnetic fields along the c axis (H || c) strongly suppress the FM fluctuations and that the superconductivity is observed in the limited magnetic field region where the longitudinal FM spin fluctuations are active. These results combined with model calculations strongly suggest that the longitudinal FM spin fluctuations tuned by H || c induce the unique spin-triplet superconductivity in UCoGe. This is the first clear example that FM fluctuations are intimately related with superconductivity., Comment: 4 pages, 5 figures, to appear in PRL

Published
2011
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23. Microscopic Evidence of Direct Coupling between Magnetic and Superconducting Order Parameters in BaFe$_2$(As$_{1-x}$P$_x$)$_2$

Author

Iye, T., Nakai, Y., Kitagawa, S., Ishida, K., Kasahara, S., Shibauchi, T., Matsuda, Y., and Terashima, T.

Subjects
Condensed Matter - Superconductivity, Condensed Matter - Strongly Correlated Electrons
Abstract

The coexistence of magnetism and superconductivity in the isovalent-P-substituted BaFe$_2$(As$_{1-x}$P$_x$)$_2$ has been investigated microscopically by $^{31}$P-NMR measurements. We found that superconducting (SC) transition occurs in a magnetic region with static ordered moments and that the moments are reduced below the SC transition temperature $T_{\rm c}$ in the samples near the phase boundary of magnetism and superconductivity. Our results indicate that magnetism and superconductivity coexist spatially but compete with each other on the same Fermi surfaces. The coexistence state is qualitatively different from that observed in other unconventional superconductors and gives a strict constraint on the theoretical model for superconductivity in BaFe$_2$(As$_{1-x}$P$_x$)$_2$., Comment: 4 pages, 3 figures

Published
2011
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24. Metamagnetic Behavior and Kondo Breakdown in Heavy-Fermion CeFePO

Author

Kitagawa, S., Ikeda, H., Nakai, Y., Hattori, T., Ishida, K., Kamihara, Y., Hirano, M., and Hosono, H.

Subjects
Condensed Matter - Strongly Correlated Electrons
Abstract

We report that nonmagnetic heavy-fermion (HF) iron oxypnictide CeFePO with two-dimensional XY-type anisotropy shows a metamagnetic behavior at the metamagnetic field H_M \simeq 4 T perpendicular to the c-axis and that a critical behavior is observed around H_M. Although the magnetic character is entirely different from that in other Ce-based HF metamagnets, H_M in these metamagnets is linearly proportional to the inverse of the effective mass, or to the temperature where the susceptibility shows a peak. This finding suggests that H_M is a magnetic field breaking the local Kondo singlet, and the critical behavior around H_M is driven by the Kondo breakdown accompanied by the Fermi-surface instability., Comment: 5pages, 6 figures published in Phys. Rev. Lett

Published
2011
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25. Non-magnetic pair-breaking effect on La(Fe_{1-x}Zn_{x})AsO_{0.85} studied by NMR and NQR

Author

Kitagawa, S., Nakai, Y., Iye, T., Ishida, K., Guo, Y. F., Shi, Y. G., Yamaura, K., and Takayama-Muromachi, E.

Subjects
Condensed Matter - Superconductivity, Condensed Matter - Strongly Correlated Electrons
Abstract

$^{75}$As and $^{139}$La NMR and nuclear quadrupole resonance (NQR) studies on Zn-substituted LaFeAsO$_{0.85}$ have been performed to investigate the Zn-impurity effects microscopically. Although superconductivity in LaFeAsO$_{0.85}$ disappears by 3% Zn substitution, we found that NMR/NQR spectra and NMR physical quantities in the normal state are hardly changed, indicating that the crystal structure and electronic states are not modified by Zn substitution. Our results suggest that the suppression of superconductivity by Zn substitution is not due to the change of the normal-state properties, but due to strong non-magnetic pair-breaking effect to superconductivity., Comment: 5 pages, 4 figures, This paper was chosen as "Paper of Editors' Suggestion"

Published
2011
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26. Abrupt recovery of Fermi-liquid transport by the c-axis collapse in CaFe2(As1-xPx)2 single crystals

Author

Kasahara, S., Shibauchi, T., Nakai, Y., Hashimoto, K., Ikeda, H., Terashima, T., and Matsuda, Y.

Subjects
Condensed Matter - Superconductivity, Condensed Matter - Strongly Correlated Electrons
Abstract

Single crystals of CaFe$_2$(As$_{1-x}$P$_x$)$_2$ are found to exhibit the tetragonal (T) to collapsed-tetragonal (cT) transition at $T_{\rm cT} \lesssim100$\,K for $x>0.05$. The c-axis shrinks by $\sim9$% below $T_{\rm cT}$, which substantially diminishes the interband nesting between the hole and electron bands. In sharp contrast to the superconducting T phase of $A$Fe$_2$(As$_{1-x}$P$_x$)$_2$ ($A=$ Ba, Sr), where the anomalous non-Fermi liquid transport properties are observed, the resistivity, Hall coefficient, and magnetoresistance data in the Ca-based system all indicate that the standard Fermi liquid behaviors are recovered abruptly below $T_{\rm cT}$, and the superconductivity disappears completely. The intimate link between the superconductivity and the non-Fermi liquid transport enlightens the essential role of interband-associated fluctuation effects in Fe-pnictides., Comment: 4 pages, 4 figures

Published
2010
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27. Anisotropic magnetic fluctuations in the ferromagnetic superconductor UCoGe studied by angle-resolved ^{59}Co NMR

Author

Ihara, Y., Hattori, T., Ishida, K., Nakai, Y., Osaki, E., Deguchi, K., Sato, N. K., and Satoh, I.

Subjects
Condensed Matter - Superconductivity, Condensed Matter - Strongly Correlated Electrons
Abstract

We have carried out direction-dependent ^{59}Co NMR experiments on a single crystal sample of the ferromagnetic superconductor UCoGe in order to study the magnetic properties in the normal state. The Knight shift and nuclear spin-lattice relaxation rate measurements provide microscopic evidence that both static and dynamic susceptibilities are ferromagnetic with strong Ising anisotropy. We discuss that superconductivity induced by these magnetic fluctuations prefers spin-triplet pairing state., Comment: 4 pages, 4 figures

Published
2010
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28. Anisotropic Superconducting Properties of Optimally Doped BaFe$_2$(As$_{0.65}$P$_{0.35}$)$_2$ under Pressure

Author

Goh, Swee K., Nakai, Y., Ishida, K., Klintberg, L. E., Ihara, Y., Kasahara, S., Shibauchi, T., Matsuda, Y., and Terashima, T.

Subjects
Condensed Matter - Superconductivity, Condensed Matter - Strongly Correlated Electrons
Abstract

Magnetic measurements on optimally doped single crystals of BaFe$_2$(As$_{1-x}$P$_{x}$)$_2$ ($x\approx0.35$) with magnetic fields applied along different crystallographic axes were performed under pressure, enabling the pressure evolution of coherence lengths and the anisotropy factor to be followed. Despite a decrease in the superconducting critical temperature, our studies reveal that the superconducting properties become more anisotropic under pressure. With appropriate scaling, we directly compare these properties with the values obtained for BaFe$_2$(As$_{1-x}$P$_{x}$)$_2$ as a function of phosphorus content., Comment: 5 pages, 3 figures

Published
2010
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29. Unconventional superconductivity and antiferromagnetic quantum critical behavior in the isovalent-doped BaFe2(As1-xPx)2

Author

Nakai, Y., Iye, T., Kitagawa, S., Ishida, K., Ikeda, H., Kasahara, S., Shishido, H., Shibauchi, T., Matsuda, Y., and Terashima, T.

Subjects
Condensed Matter - Superconductivity, Condensed Matter - Strongly Correlated Electrons
Abstract

Spin dynamics evolution of BaFe$_2$(As$_{1-x}$P$_x$)$_2$ was probed as a function of P concentration via $^{31}$P NMR. Our NMR study reveals that two-dimensional antiferromagnetic (AF) fluctuations are notably enhanced with little change in static susceptibility on approaching the AF phase from the superconducting dome. Moreover, magnetically ordered temperature $\theta$ deduced from the relaxation rate vanishes at optimal doping. These results provide clear-cut evidence for a quantum-critical point (QCP), suggesting that the AF fluctuations associated with the QCP play a central role in the high-$T_c$ superconductivity., Comment: 5 pages, 3 figures

Published
2010
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30. Nonlinearly Realized Extended Supergravity

Author

Izawa, K. -I., Nakai, Y., and Takahashi, Ryo

Subjects
High Energy Physics - Phenomenology
Abstract

We provide nonlinear realization of supergravity with an arbitrary number of supersymmetries by means of coset construction. The number of gravitino degrees of freedom counts the number of supersymmetries, which will be possibly probed in future experiments. We also consider goldstino embedding in the construction to discuss the relation to nonlinear realization with rigid supersymmetries., Comment: 19 pages

Published
2010
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31. Studying Gaugino Mass in Semi-Direct Gauge Mediation

Author

Ibe, M., -I., Izawa K., and Nakai, Y.

Subjects
High Energy Physics - Phenomenology, High Energy Physics - Theory
Abstract

We study gaugino mass generation in the context of semi-direct gauge mediation models, where the messengers are charged under both the hidden sector and the standard model gauge groups while they do not play important roles in dynamical supersymmetry breaking. We clarify the cancellation of the leading contributions of the supersymmetry breaking effects to the gaugino mass in this class of models in terms of the macroscopic effective theory of the hidden sector dynamics. We also consider how to retrofit the model so that we obtain the non-vanishing leading contribution to the gaugino mass., Comment: 14 pages

Published
2009
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34. Strongly Coupled Semi-Direct Mediation of Supersymmetry Breaking

Author

Ibe, M., Izawa, K. -I., and Nakai, Y.

Subjects
High Energy Physics - Phenomenology
Abstract

Strongly coupled semi-direct gauge mediation models of supersymmetry breaking through massive mediators with standard model charges are investigated by means of composite degrees of freedom. Sizable mediation is realized to generate the standard model gaugino masses for a small mediator mass without breaking the standard model symmetries., Comment: 7 pages; v2: the model generalized, gaugino mass corrected; v3: explanations expanded, references added

Published
2008
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35. Comparison of cancer detection rates by transrectal prostate biopsy for prostate cancer using two different nomograms based on patient’s age and prostate volume

Author

Hori S, Tanaka N, Nakai Y, Morizawa Y, Tatsumi Y, Miyake M, Anai S, Fujii T, Konishi N, Nakagawa Y, Hirao S, and Fujimoto K

Subjects
age, cancer detection rate, nomogram, prostate cancer, prostate volume, transrectal prostate biopsy, Diseases of the genitourinary system. Urology, RC870-923
Abstract

Shunta Hori,1 Nobumichi Tanaka,1 Yasushi Nakai,1 Yosuke Morizawa,1 Yoshihiro Tatsumi,1 Makito Miyake,1 Satoshi Anai,1 Tomomi Fujii,2 Noboru Konishi,2 Yoshinori Nakagawa,3 Syuya Hirao,4 Kiyohide Fujimoto1 1Department of Urology, Nara Medical University, Kashihara, Nara 634-8522, Japan; 2Department of Pathology, Nara Medical University, Kashihara, Nara 634-8522, Japan; 3Department of Urology, Yamatotakada Municipal Hospital, Yamatotakada, Nara 635-8501, Japan; 4Department of Urology, Medical Corporation Katsurakai HIRAO Hospital, Kashihara, Nara 634-0076, Japan Background: The aim of this study is to evaluate the efficacy of two different Nara Urological Research and Treatment Group (NURTG) nomograms allocating 6–12 biopsy cores based on age and prostate volume. Materials and methods: From April 2006 to July 2014, a total of 1,605 patients who underwent initial prostate biopsy were enrolled. Based on a nomogram taking the patient’s age and prostate volume into consideration, 6–12 biopsy cores were allocated. Two types of nomogram were used, for the former group (before March 2009) and latter group (March 2009 onward). Cancer detection rates in all patients and those with prostate-specific antigen values in the gray zone (4.0–10 ng/mL) were compared. Predictive parameters for detection of prostate cancer in gray-zone patients were also investigated. Results: The cancer detection rates in all patients and those in the gray zone were 48% and 38% in the former group and 54% and 41% in the latter group, respectively. The cancer detection rate in all patients was significantly higher in the latter group compared with the former group, but detection in gray-zone patients did not show a significant difference between the two groups (P=0.011 and P=0.37, respectively). Multivariate analysis indicated that age, digital rectal examination, prostate volume, transrectal ultrasonography findings, and volume/biopsy ratio were significant predictive parameters in gray-zone patients. The clinically insignificant cancer detection rate was significantly lower in the latter group compared with the former group (P=0.0008). Conclusion: The latter nomogram provided more acceptable detection rates of clinically significant and insignificant cancer than the former one, and we consider that an initial maximum 12-core transrectal ultrasound-guided needle biopsy may be sufficient for prostate cancer diagnosis. Keywords: age, cancer detection rate, nomogram, prostate cancer, prostate volume, transrectal prostate biopsy

Published
2019

36. Emerging biomarkers for the diagnosis and monitoring of urothelial carcinoma

Author

Miyake M, Owari T, Hori S, Nakai Y, and Fujimoto K

Subjects
urothelial carcinoma, bladder cancer, upper urinary tract carcinoma, biomarker, diagnosis, surveillance, Diseases of the genitourinary system. Urology, RC870-923
Abstract

Makito Miyake, Takuya Owari, Shunta Hori, Yasushi Nakai, Kiyohide Fujimoto Department of Urology, Nara Medical University, Kashihara-shi, Nara 634-8522, Japan Abstract: Urothelial carcinoma (UC) arises extensively from the renal pelvis, ureter, urinary bladder, and urethra. UC represents a clinical and social challenge because of its incidence, post-treatment recurrence rate, and prognosis. Combinations of urine cytology, cystoscopy, and conventional imaging such as computed tomography are currently used for diagnosis and monitoring modalities of UC. Both the poor diagnostic accuracy of urine cytology and poor cost performance of cystoscopy and conventional imaging modalities emphasize the urgent need for advancement in clinical guidance for UC. Urine- and blood-based biomarkers for detection of UC of the bladder and upper urinary tract represent a considerable research area. Biomarkers can help to improve UC diagnosis with the aim of replacing cystoscopy and other imaging examinations in future and may enable individualizing risk stratification regarding therapy and follow-up. Over the decades, numerous studies have focused on the potential application of biomarkers for UC, including urine, circulating tumor DNA, RNAs, proteins, and extracellular vesicles. Although some biomarkers such as ImmunoCyt/uCyt+, UroVysion, NMP-22, bladder tumor antigen, CxBladder, and Xpert Bladder Cancer are currently available in clinical practice, few biomarkers achieve high sensitivity and specificity. Emerging biomarkers are continuously developed and reported in medical journals. However, there is a significant lack on following external validation using different cohorts. The positive results are needed to be confirmed by more studies with large-scale cohorts and long follow-up periods to prove the true value of novel biomarkers, followed by their adoption in clinical practice. The present paper provides an overview of the evidence based on high-impact studies regarding urine- and blood-based biomarkers and their clinical applications in bladder cancer and upper tract UC. Keywords: urothelial carcinoma, bladder cancer, upper urinary tract cancer, biomarker, diagnosis, surveillance

Published
2018

37. Thermopower of CexR1-xB6 (R=La, Pr and Nd)

Author

Kim, M. S., Nakai, Y., Tou, H., Sera, M., Iga, F., Takabatake, T., and Kunii, S.

Subjects
Condensed Matter - Strongly Correlated Electrons
Abstract

The thermopower, S, of CexR1-xB6 (R=La, Pr, Nd) was investigated. S with a positive sign shows a typical behavior observed in the Ce Kondo system, an increase with decreasing temperature at high temperatures and a maximum at low temperatures. The S values of all the systems at high temperatures are roughly linearly dependent on the Ce concentration, indicating the conservation of the single-impurity character of the Kondo effect in a wide x range. However, the maximum value of S, S_max, and the temperature, T_max, at which S_max is observed exhibit different x dependences between CexLa1-xB6 and CexR1-xB6 (R=Pr, Nd). In CexLa1-xB6, T_max, which is ~8 K in CeB6, decreases with decreasing x and converges to ~1 K in a very dilute alloy and S_max shows an increase below x ~ 0.1 after decreasing with decreasing x. In CexR1-xB6 (R=Pr, Nd), T_max shows a weak x dependence but S_max shows a roughly linear decrease in x. These results are discussed from the standpoint of the chemical pressure effect and the Ce-Ce interaction. S in the long-range ordered phase shows very different behavior between CexPr1-xB6 and CexNd1-xB6., Comment: PDF file, 7 pages with 9 figures, accepted for publication

Published
2006
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38. Evidence for s-wave superconductivity with antiferromagnetic fluctuations in filled skutterudite LaFe$_{4}$P$_{12}$: $^{139}$La and $^{31}$P-NMR studies

Author

Nakai, Y., Ishida, K., Kikuchi, D., Sugawara, H., and Sato, H.

Subjects
Condensed Matter - Strongly Correlated Electrons, Condensed Matter - Superconductivity
Abstract

We have performed $^{139}$La,$^{31}$P-NMR studies on a filled skutterudite superconductor LaFe$_{4}$P$_{12}$ with a critical temperature $T_c=4.1$ K. In the normal state, the presence of antiferromagnetic (AFM) fluctuations at finite wave vectors is suggested from the relation between the nuclear spin-lattice relaxation rate $1/T_1$ and the Knight shift. In the superconducting (SC) state, the distinct coherence peak was observed just below $T_c$, and is easily suppressed by the applied field. An exponential decrease of $1/T_1$ was observed, suggestive of the isotropic superconducting gap with $2\Delta/k_{\rm B}T_c =3.8$. Besides, we observed the decrease of the Knight shift, indicative of the singlet-pair formation below $T_c$. These results are clear evidence that LaFe$_{4}$P$_{12}$ is a rare s-wave superconductor with significant AFM fluctuations., Comment: 5 pages, 6 figures, to be published in Journal of the Physical Society of Japan, Vol.74 No.12

Published
2005
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39. In vivo visualization of epidermal growth factor receptor and survivin expression in porcine pancreas using endoscopic ultrasound guided fine needle imaging with confocal laser-induced endomicroscopy.

Author

Nakai, Y, Shinoura, S, Ahluwalia, A, Tarnawski, A S, and Chang, K J

Subjects
Animals, Endoscopic Ultrasound-Guided Fine Needle Aspiration: instrumentation, Feasibility Studies, Fluorescent Antibody Technique, Direct, Inhibitor of Apoptosis Proteins: analysis, Injections, Microscopy, Confocal: instrumentation, Molecular Imaging: instrumentation, methods, Needles, Pancreas: chemistry, cytology, Pilot Projects, Receptor, Epidermal Growth Factor: analysis, Swine
Abstract

The aims of this pilot study were to establish a principle of molecular imaging of the pancreas and determine in vivo expression of epidermal growth factor receptor (EGF-R) and survivin using a novel endoscopic ultrasound-guided fine needle imaging (EUS-FNI) technique, which incorporates needle based confocal laser-induced endomicroscopy (nCLE) after intrapancreatic injection of FTIC-labeled antibodies. Studies were performed in anesthetized pigs. FITC-labeled specific antibodies against EGF-R and survivin were injected into the tail and neck of the pancreas using a 19 gauge needle introduced under EUS guidance. Thirty minutes later, nCLE was performed using a prototype needle-based confocal laser-induced endomicroscopy probe (Cellvizio AQ-Flex-19, Mauna Kea Technologies, Paris, France) to determine cellular and tissue localization of EGF-R and survivin in the pancreas. Then pigs were euthanized and specimens of pancreas from areas injected with antibodies were obtained for histologic examination under epifluorescence microscope.EUS-guided nCLE enabled visualization of EGF-R and survivin in pancreatic tissue. Expression of EGF-R and survivin in pancreas was confirmed by histology. EGF-R immunoreactivity was localized to majority of duct-lining cells and to the surface and cytoplasm of many acinar cells. Survivin was localized mainly to the acinar cells. This study demonstrated the feasibility of in vivo, real time visualization of EGF-R and survivin in the pancreas by local injection of FITC-labeled antibodies via EUS-guided fine needle injection, followed by EUS-guided needle based confocal laser-induced endomicroscopy.

Published
2012

40. Molecular imaging of epidermal growth factor-receptor and survivin in vivo in porcine esophageal and gastric mucosae using probe-based confocal laser-induced endomicroscopy: proof of concept.

Author

Nakai, Y, Shinoura, S, Ahluwalia, A, Tarnawski, A S, and Chang, K J

Subjects
Animals, Esophagus: metabolism, Gastric Mucosa: metabolism, Keratinocytes: metabolism, Lasers, Microscopy, Confocal: methods, Molecular Imaging: methods, Pilot Projects, Receptor, Epidermal Growth Factor: metabolism, Stem Cells: metabolism, Stomach: metabolism, Swine
Abstract

Confocal laser-induced endomicroscopy (CLE) enables in vivo, real time visualization of the subsurface cells and tissue structures in gastrointestinal mucosa at a subcellular resolution of ≈1000x magnification. The aims of this pilot study were to establish a principle of molecular imaging and determine in vivo expression of epidermal growth factor receptor (EGF-R) and survivin in porcine esophageal and gastric mucosa using probe-based CLE (pCLE) and topically applied FITC-labeled antibodies. Studies were performed in anesthetized pigs. During endoscopy FITC-labeled antibodies against EGF-R and survivin were either sprayed onto esophageal and gastric mucosa in preselected areas or administered via submucosal injection. Thirty minutes later pCLE was performed using a through-the-scope probe (GastroFlex UHD, Cellvizio, Mauna Kea Technologies, Paris, France) to determine cellular and tissue localization of EGF-R and survivin. Then the pigs were euthanized and esophageal and gastric walls from the areas sprayed or injected with antibodies were collected for histologic examination under epifluorescence microscopy.CLE enabled visualization of EGF-R and survivin in esophageal and gastric mucosa and this was confirmed by histology. In the esophagus both EGF-R and survivin were localized predominantly to the keratinocyte progenitor cells. In the stomach, EGF-R was localized to progenitor zone cells and some epithelial cells. Localization of survivin was similar, but involved more surface epithelial cells. This study demonstrated feasibility of using CLE and topical administration of FITC labeled antibodies for in vivo localization of EGF-R and survivin in esophageal and gastric mucosa.

Published
2012

41. Successful salvage of allograft dysfunction triggered by transplant renal vein thrombosis immediately after kidney transplantation: a case report

Author

Hori S, Miyamoto T, Sakamoto K, Shimizu T, Ichikawa K, Morizawa Y, Gotoh D, Nakai Y, Miyake M, Yoneda T, Tanaka N, Yoshida K, and Fujimoto K

Subjects
kidney transplantation, surgical exploration, transplant renal vein thrombosis, thrombectomy, Diseases of the genitourinary system. Urology, RC870-923
Abstract

Shunta Hori, Tatsuki Miyamoto, Keiichi Sakamoto, Takuto Shimizu, Kazuki Ichikawa, Yosuke Morizawa, Daisuke Gotoh, Yasushi Nakai, Makito Miyake, Tatsuo Yoneda, Nobumichi Tanaka, Katsunori Yoshida, Kiyohide Fujimoto Department of Urology, Nara Medical University, Kashihara, Nara 634-8522, Japan Background: Transplant renal vein thrombosis (TRVT) is a severe vascular complication and is caused by various factors, including recipient factors, donor factors, immunosuppression regimens, and surgical techniques. Despite adequate interventions, including thrombolytic therapy or surgical thrombectomy, successful salvage of the allograft is often difficult. We observed a case of TRVT induced by compression of the renal vein immediately after intraoperative abdominal closure.Case presentation: A 41-year-old male underwent ABO-compatible living kidney transplantation. The donor was his 45-year-old sister, and her right kidney was donated. The allograft had a single artery and vein. One of the preoperative recipient problems was obesity (body mass index, 33.4 kg/m2). Intraoperative Doppler ultrasonography (US) revealed sufficient blood flow throughout the allograft, and urine output was also observed. After surgery, hematuria was observed; the urine output decreased and serum creatinine levels increased to 7.0 mg/dL. Doppler US showed a decrease in diastolic flow and an elevated resistive index, which were similar findings to those noted in acute rejection. Although steroid pulse therapy was initiated, allograft dysfunction was worsening. On postoperative day 4, surgical exploration revealed TRVT; consequently, thrombectomy was performed. The urine output increased, and serum creatinine levels decreased to 1.8 mg/dL. The cause of TRVT development may be that the transplant renal vein was relatively short, due to the right kidney being compressed by surrounding tissues after abdominal closure, and that TRVT was gradually developing due to stagnant blood flow.Conclusion: Although TRVT is induced by multiple factors, an accurate diagnosis is often difficult. Understanding these factors, including obesity, and considering TRVT as a cause of allograft dysfunction are important during the pre-, peri-, and postoperative periods. Knowledge of TRVT can lead to early and accurate diagnosis and intervention, resulting in better outcomes for the patients with allograft dysfunction. Keywords: kidney transplantation, surgical exploration, transplant renal vein thrombosis, thrombectomy

Published
2018

42. Quality of life worsened the most severely in patients immediately after intensity-modulated radiation therapy for prostate cancer

Author

Nakai Y, Tanaka N, Anai S, Miyake M, Asakawa I, Morizawa Y, Hori S, Torimoto K, Fujii T, Hasegawa M, and Fujimoto K

Subjects
chronological changes, intensity-modulated radiation therapy, prostate cancer, quality of life, radiation therapy, Diseases of the genitourinary system. Urology, RC870-923
Abstract

Yasushi Nakai,1 Nobumichi Tanaka,1 Satoshi Anai,1 Makito Miyake,1 Isao Asakawa,2 Yosuke Morizawa,1 Shunta Hori,1 Kazumasa Torimoto,1 Tomomi Fujii,3 Masatoshi Hasegawa,2 Kiyohide Fujimoto1 1Department of Urology, Nara Medical University, Nara, Japan; 2Department of Radiation Oncology, Nara Medical University, Nara, Japan; 3Department of Pathology, Nara Medical University, Nara, Japan Purpose: The aim of this study was to evaluate the chronological changes in lower urinary tract symptoms (LUTSs), disease-related quality of life (QOL), and health-related QOL (HR-QOL) of patients who received intensity-modulated radiotherapy (IMRT).Patients and methods: In 121 patients who had received IMRT and were followed up for >2 years, the International Prostate Symptom Score (IPSS), Overactive Bladder Symptom Score (OABSS), Expanded Prostate Cancer Index Composite (EPIC), and 8-Item Short-Form Health Survey (SF-8) were used before IMRT, at the halfway point in IMRT, immediately after IMRT, and 1–24 months after the completion of IMRT.Results: The IPSS and OABSS and the urinary and bowel domains of the EPIC indicated that QOL worsened at the halfway point in IMRT, further worsened more severely immediately after IMRT, and then improved. The sexual domain of the EPIC significantly decreased at the halfway point in IMRT, which significantly lowered until 24 months. The scores of physical functioning, role physical, bodily pain, vitality, social functioning, and role emotional domains in the SF-8 significantly decreased and reached their lowest points immediately after IMRT.Conclusion: QOL worsened the most severely in patients immediately after IMRT for prostate cancer. This knowledge can influence treatment recommendations and enable patients to make better informed decisions. Keywords: chronological changes, intensity-modulated radiotherapy, prostate cancer, quality of life, radiotherapy

Published
2018

43. Colony-stimulating factors detected in tumor cells and voided urine are potential prognostic markers for patients with muscle-invasive bladder cancer undergoing radical cystectomy

Author

Morizawa Y, Miyake M, Shimada K, Hori S, Tatsumi Y, Nakai Y, Tanaka N, Fujii T, and Fujimoto K

Subjects
colony stimulating factor, M-CSF, G-CSF, GM-CSF, muscle-invasive bladder cancer, radical cystectomy, Diseases of the genitourinary system. Urology, RC870-923
Abstract

Yosuke Morizawa,1 Makito Miyake,1 Keiji Shimada,2 Shunta Hori,1 Yoshihiro Tatsumi,1 Yasushi Nakai,1 Nobumichi Tanaka,1 Tomomi Fujii,3 Kiyohide Fujimoto1 1Department of Urology, Nara Medical University, Nara, Japan; 2Department of Pathology, Nara City Hospital, Nara, Japan; 3Department of Diagnostic Pathology, Nara Medical University, Nara, Japan Background: The clinical use of macrophage colony-stimulating factor, granulocyte colony-stimulating factor (G-CSF), and granulocyte macrophage colony-stimulating factor (GM-CSF) has improved the safety of cytotoxic chemotherapy. However, the overexpression of these CSFs in cancers has been reported to be associated with a poor prognosis in various malignancies. We evaluated the potential of CSF expression as a predictor of clinical outcome in patients with muscle-invasive bladder cancer (MIBC).Methods: Consecutive patients (n=58) with MIBC who underwent radical cystectomy (RC) were included in this retrospective study. Treatment-naïve tumor specimens obtained by initial transurethral resection of bladder tumors prior to RC were immunostained with antibodies against macrophage colony-stimulating factor, G-CSF, and GM-CSF. We compared the clinicopathological variables and survival between these groups. Baseline levels of CSFs in the serum and voided urine were quantified using an enzyme-linked immunosorbent assay and compared with the expression of CSFs in the tumor lesions.Results: Low expression of GM-CSF in the tumor cells was significantly correlated with a pathological T4 category (vs T2–3; P=0.02). In univariate survival analysis, high G-CSF and low GM-CSF expression in the tumor lesion were associated with poor outcomes. Furthermore, Cox proportional regression analysis revealed that high G-CSF and low GM-CSF expression in the tumor were independent predictors of shorter recurrence-free survival, cancer-specific survival, and overall survival. The levels of CSFs in voided urine were associated with the expression of CSFs in the tumor lesions.Conclusion: GM-CSF and G-CSF expression in the tumor lesions obtained by initial transurethral resection are independent predictors of poor outcome in MIBC after RC. Levels of G-CSF and GM-CSF in urine before treatment could be useful in prognostication. Keywords: colony-stimulating factor, M-CSF, G-CSF, GM-CSF, muscle-invasive bladder cancer, radical cystectomy

Published
2018

47. A PTHrP Gradient Drives Mandibular Condylar Chondrogenesis via Runx2.

Author

Tsutsumi-Arai, C., Arai, Y., Tran, A., Salinas, M., Nakai, Y., Orikasa, S., Ono, W., and Ono, N.

Subjects
CHONDROGENESIS, PARATHYROID hormone-related protein, MANDIBULAR condyle, MANDIBULAR ramus, BONE growth
Abstract

The mandibular condylar cartilage (MCC) is an essential component of the temporomandibular joint, which orchestrates the vertical growth of the mandibular ramus through endochondral ossification with distinctive modes of cell differentiation. Parathyroid hormone–related protein (PTHrP) is a master regulator of chondrogenesis; in the long bone epiphyseal growth plate, PTHrP expressed by resting zone chondrocytes promotes chondrocyte proliferation in the adjacent layer. However, how PTHrP regulates chondrogenesis in the MCC remains largely unclear. In this study, we used a Pthrp-mCherry knock-in reporter strain to map the localization of PTHrP+ cells in the MCC and define the function of PTHrP in the growing mandibular condyle. In the postnatal MCC of Pthrp mCherry/+ mice, PTHrP-mCherry was specifically expressed by cells in the superficial layer immediately adjacent to RUNX2-expressing cells in the polymorphic layer. PTHrP ligands diffused across the polymorphic and chondrocyte layers where its cognate receptor PTH1R was abundantly expressed. We further analyzed the mandibular condyle of Pthrp mCherry/mCherry mice lacking functional PTHrP protein (PTHrP-KO). At embryonic day (E) 18.5, the condylar process and MCC were significantly truncated in the PTHrP-KO mandible, which was associated with a significant reduction in cell proliferation across the polymorphic layer and a loss of SOX9+ cells in the chondrocyte layers. The PTHrP-KO MCC showed a transient increase in the number of Col10a1+ hypertrophic chondrocytes at E15.5, followed by a significant loss of these cells at E18.5, indicating that superficial layer–derived PTHrP prevents premature chondrocyte exhaustion in the MCC. The expression of Runx2, but not Sp7, was significantly reduced in the polymorphic layer of the PTHrP-KO MCC. Therefore, PTHrP released from cells in the superficial layer directly acts on cells in the polymorphic layer to promote proliferation of chondrocyte precursor cells and prevent their premature differentiation by maintaining Runx2 expression, revealing a unique PTHrP gradient-directed mechanism that regulates MCC chondrogenesis. [ABSTRACT FROM AUTHOR]

Published
2024
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48. Atypical small acinar proliferation and two or more cores of high-grade intraepithelial neoplasia on a previous prostate biopsy are significant predictors of cancer during a transperineal template-guided saturation biopsy aimed at sampling one core for each 1 mL of prostate volume

Author

Nakai Y, Tanaka N, Miyake M, Hori S, Tatsumi Y, Morizawa Y, Fujii T, Konishi N, and Fujimoto K

Subjects
Atypical small acinar proliferation, high-grade intraepithelial neoplasia, transperineal template-guided saturation biopsy, prostate cancer, repeat biopsy, Diseases of the genitourinary system. Urology, RC870-923
Abstract

Yasushi Nakai,1 Nobumichi Tanaka,1 Makito Miyake,1 Shunta Hori,1 Yoshihiro Tatsumi,1,2 Yosuke Morizawa,1 Tomomi Fujii,2 Noboru Konishi,2 Kiyohide Fujimoto1 1Department of Urology, Nara Medical University, 2Department of Pathology, Nara Medical University, Kashihara-shi, Nara, Japan Objective: The objective of this study was to evaluate whether high-grade prostatic intraepithelial neoplasia (HGPIN) and atypical small acinar proliferation (ASAP) predict prostate cancer (PCa) during repeat transperineal template saturation biopsy with a high number of cores per prostate volume in patients with persistent clinical suspicion of PCa who underwent at least one previous negative transrectal ultrasound (TRUS)-guided biopsy. Methods: We retrospectively evaluated 135 consecutive patients with persistent clinical suspicion of PCa, despite a set of negative TRUS-guided biopsies and increasing prostate-specific antigen levels; abnormal findings on digital rectal examination, TRUS, or magnetic resonance imaging; previous biopsy showing HGPIN; and previous biopsy showing atypical glands. Transperineal template saturation biopsy (TTSB) was performed at 5mm intervals to sample one core for each 1 mL of prostate volume. Results: The median rate of biopsy cores per prostate volume was 1.00 (range: 0.75–1.39). The PCa detection rates in patients who were diagnosed with HGPIN, or had two or more cores of HGPIN or ASAP, were 53% (9/17), 89% (8/9), and 83% (10/12), respectively. Two or more HGPIN cores and ASAP were positive predictors of PCa on TTSB. The high-grade cancer rates (Gleason score [GS] ≥7) in patients with ASAP and two or more cores of HGPIN were 20% and 80%, respectively. The cancer detection rate represented by a GS score ≥8 in patients with ASAP or two or more cores of HGPIN at a previous TRUS-guided biopsy was 5.5% (1/18). Conclusion: ASAP or two or more cores of HGPIN at a previous TRUS-guided biopsy strongly indicated the presence of PCa on TTSB. Keywords: atypical small acinar proliferation, high-grade intraepithelial neoplasia, transperineal template-guided saturation biopsy, prostate cancer, repeat biopsy

Published
2017

49. Associations among depressive symptoms, childhood abuse, neuroticism, and adult stressful life events in the general adult population

Author

Ono K, Takaesu Y, Nakai Y, Shimura A, Ono Y, Murakoshi A, Matsumoto Y, Tanabe H, Kusumi I, and Inoue T

Subjects
Childhood abuse, Depression, Neuroticism, Stressful life events, Structural equation modeling (SEM), Neurosciences. Biological psychiatry. Neuropsychiatry, RC321-571, Neurology. Diseases of the nervous system, RC346-429
Abstract

Kotaro Ono,1 Yoshikazu Takaesu,1 Yukiei Nakai,2 Akiyoshi Shimura,1 Yasuyuki Ono,1 Akiko Murakoshi,1 Yasunori Matsumoto,1 Hajime Tanabe,3 Ichiro Kusumi,2 Takeshi Inoue1 1Department of Psychiatry, Tokyo Medical University, Tokyo, 2Department of Psychiatry, Hokkaido University Graduate School of Medicine, Hokkaido, 3Department of Clinical Human Sciences, Graduate school of Humanities and Social Sciences, Shizuoka University, Shizuoka, Japan Background: Recent studies have suggested that the interactions among several factors affect the onset, progression, and prognosis of major depressive disorder. This study investigated how childhood abuse, neuroticism, and adult stressful life events interact with one another and affect depressive symptoms in the general adult population. Subjects and methods: A total of 413 participants from the nonclinical general adult population completed the Patient Health Questionnaire-9, the Child Abuse and Trauma Scale, the neuroticism subscale of the shortened Eysenck Personality Questionnaire – Revised, and the Life Experiences Survey, which are self-report scales. Structural equation modeling (Mplus version 7.3) and single and multiple regressions were used to analyze the data. Results: Childhood abuse, neuroticism, and negative evaluation of life events increased the severity of the depressive symptoms directly. Childhood abuse also indirectly increased the negative appraisal of life events and the severity of the depressive symptoms through enhanced neuroticism in the structural equation modeling. Limitations: There was recall bias in this study. The causal relationship was not clear because this study was conducted using a cross-sectional design. Conclusion: This study suggested that neuroticism is the mediating factor for the two effects of childhood abuse on adulthood depressive symptoms and negative evaluation of life events. Childhood abuse directly and indirectly predicted the severity of depressive symptoms. Keywords: childhood abuse, depression, neuroticism, stressful life events, structural equation modeling

Published
2017

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